Vibration dampener for coil tension window balance spring

Abstract

Molded resin vibration dampener is mounted on coiled tension window balance springs arranged within spring covers. A resin wall of the vibration dampener, shaped for fitting around the tension spring, has a slot oriented longitudinally of the spring, and the wall is flexible enough to allow the slot to be spread open so that the body can be pressed onto a mid-region of the spring. Resilient fins extend obliquely outward from the body far enough to engage an interior surface of the spring cover and thereby hold the body and the spring spaced away from the spring cover to prevent rattling of the spring within the cover.

We claim: 
     
       1. A vibration dampener for a coiled tension window balance spring within a spring cover, said vibration dampener comprising: a. a resin body having a wall shaped for fitting around said coiled tension spring;   b. said wall having a slot oriented longitudinally of said spring when said body is mounted on said spring;   c. said wall being flexible enough to allow said slot to spread open so that said body can be pressed onto a mid region of said spring;   d. resilient fins extending obliquely outward from said body; and   e. when said body is mounted on said spring, said fins extending far enough from said body to flexibly engage an interior surface of said spring cover and thereby hold said body and said spring spaced away from said interior surface of said spring cover to prevent rattling of said spring within said cover.   
     
     
       2. The vibration dampener of claim 1 wherein said fins extend outward from a fin end of said body, and said slot has a flare at a nose end of said body opposite said fin end of said body, said flare allowing said nose end of said body to be pressed foremost onto said spring for flexing said wall to spread open said slot as said body is pressed onto said spring. 
     
     
       3. The vibration dampener of claim 1 wherein said body has an internal projection oriented radially inward to extend between turns of said spring and hold said body against longitudinal movement along said spring. 
     
     
       4. The vibration dampener of claim 3 wherein said projection is shaped for detenting between said turns of said spring. 
     
     
       5. The vibration dampener of claim 3 wherein said projection is arranged adjacent said slot to slide in between coils of said spring as said body is pressed onto said spring. 
     
     
       6. The vibration dampener of claim 1 wherein said fins taper to become thinner with greater distance outward from said body. 
     
     
       7. The vibration dampener of claim 1 wherein said body wall is generally cylindrical. 
     
     
       8. The vibration dampener of claim 7 wherein said fins extend outward from a fin end of said body, and said slot has a flare at a nose end of said body opposite said fin end of said body, said flare allowing said nose end of said body to be pressed foremost onto said spring for flexing said wall to spread open said slot as said body is pressed onto said spring. 
     
     
       9. The vibration dampener of claim 8 wherein said fins taper to become thinner with greater distance outward from said body. 
     
     
       10. The vibration dampener of claim 8 wherein said body has an internal projection oriented radially inward to extend between turns of said spring and hold said body against longitudinal movement along said spring. 
     
     
       11. The vibration dampener of claim 10 wherein said projection is shaped for detenting between said turns of said spring. 
     
     
       12. The vibration dampener of claim 10 wherein said projection is arranged adjacent said slot to slide in between coils of said spring as said body is pressed onto said spring. 
     
     
       13. The vibration dampener of claim 11 wherein said projection is shaped for detenting between said turns of said spring. 
     
     
       14. The vibration dampener of claim 13 wherein said fins taper to become thinner with greater distance outward from said body.